Novel three-dimensional microengineering techniques

The techniques of photolithography and vacuum coating have been investigated, primarily as a means of producing three-dimensional structures.

Using ultra-smooth glass capillary tubes as a substrate, and a rotational drive system, multiple free-standing cylinders can be fabricated on the surface. These are produced by a combination of metallisation and photolithography to accurately define the desired structure with precise edge definition.

Owing to the rotary motion of the photolithography technique, it was found that by changing the physical shape of the mask directly varied the exposure time at different points, forming structures with definable surface topographies (e.g. cylinders with blazed or stepped cross-sections along their length).

The advantages and limitations of these techniques are presented, highlighting the fabrication processes currently being developed to realise novel structures.